Polyol compositions for hot melt adhesives

ABSTRACT

Disclosed are polyether and polyesters polyol condensations. The polyols are uniquely suited for ease of manufacture and improved adhesive characteristics particularly for low surface energy materials. The materials can be used in urethane adhesives.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional PatentApplication Ser. No. 61/942,786, filed Feb. 21, 2014, which applicationis hereby incorporated by reference in its entirety.

FIELD OF THE INVENTION

The compositions relate to polyol materials. The polyols are polymericacid or hydroxyl terminated materials that are end capped. The polymerpolyols can be used with a reactive curing agent such as an isocyanatecompounds or used in formulated curable adhesives.

BACKGROUND OF THE INVENTION

In the preparation of polyether and polyester polyol materials, andparticularly in the manufacture of polyester materials, control of acidnumber, hydroxyl number, reaction conditions and molecular weight can beimportant in order to increase polyol productivity. Improved polyolmaterials can also produce improved adhesive properties in theformulated curable adhesive materials, including urethane adhesives.

While a number of polyether and polyester polyols have been formulated,a substantial need still exists in obtaining improved polyether andpolyester polyol preparation or processing that can improvemanufacturing efficiency, control of acid number or hydroxyl number andmolecular weight. A further need exists to obtain improved adhesiveproperties in a final adhesive formulation.

BRIEF DISCLOSURE

We have found that the use of a glycidyl ether or ester compound as acapping agent can improve the manufacture of and the properties ofpolymer polyol compounds. Capped polyol compositions of the disclosureare substantially linear polyether or polyester polyols with an acidnumber equal to or less than about 2 or a hydroxyl number equal to orgreater than 10 shows improved properties when used in curable (i.e.)polyurethane adhesive materials. The capped polyols when used withsuitable isocyanate reactive compounds produce improved adhesivestrength in bonding particularly low surface energy materials such aspolyolefins and ABS resins.

The processes for manufacturing the polyol compositions and specificallypolyester polyol materials are improved in terms of efficiency andyield.

Polyether polyols are typically made by polymerizing alkylene oxidematerials to form substantially linear polymers.

Polyester polyols can be made by polymerizing multifunctional aliphaticor aromatic carboxylic acids (two or more carboxylic groups) with amultifunctional aliphatic or aromatic alcohol (two or more hydroxylgroups) compounds resulting in polyester materials having residualacidic or hydroxyl functionality, measured by acid number or hydroxylnumber. Lower alcohol esters of the carboxylic acids can be used in thepoly-esterification.

We have found that useful precursor polyester polyol materials having anacid number or hydroxyl number of about 5 to 30 can be reacted with aglycidyl compound. The amount of glycidyl compound is used that reactswith residual active hydrogen (acid or hydroxyl) to cap the polymer andcomplete the reaction but leaving sufficient hydroxyl to be useful in areaction with isocyanate. The use of the glycidyl compound can alsoprovide the manufacture of the polyol material with molecular weightcontrol and improved adhesive properties. In the polyester, the moleratio of hydroxyl:carboxyl (—OH:—CO₂H) can be 1.2:1 to 0.8:1 or 1.1:1 to0.9:1. The molecular weight (M_(n)) of the capped material is greaterthan 500 and is often 1000 to 16000 or 2000 to 4000.

We have further found in manufacture of polyester polyols particularlyfrom dicarboxylic acids and di-hydroxyl compounds that the glycidylester compound can be used to substantially reduce manufacturing time,control molecular weight and improve the properties of the resultingadhesive materials. The use of the glycidyl capping agent results inreduced reaction time and increased productivity. The glycidyl compoundpermits the reaction to end before all consuming the maximum amount ofthe reactants. As the concentration of the reactants is reduced by theesterification, the reaction rate slows. At this point, if the molecularweight is sufficient, the glycidyl agent can be used to react withremaining active hydrogen compound to compete the synthesis. Molecularweights are measured as number average (M_(n)). In this way the reactiondoes not need to be driven to completion. Amounts of materials areselected such that the hydroxyl or acid number of the finished materialsis sufficient to react with (e.g.) an isocyanate compound in aformulated adhesive.

BRIEF DESCRIPTION OF DRAWINGS

Certain viscosity and reaction characteristics of the claimed adhesivesare shown in FIGS. 1 and 2, respectively.

FIG. 1 is a graph showing a relationship between viscosity and averagemolecular weight for a precursor (linear) polyester and a cappedpolyester.

FIG. 2 is a graph showing temperature versus reaction time andtemperature versus weight of water collected from the reactor forseveral reaction conditions of Polyester 17.

DETAILED DISCUSSION

In a first aspect of the invention is a generic polymeric polyolprecursor compound having an acid number or a hydroxyl number of about 5to 30 that can be reacted with a glycidyl compound resulting in end capof the polyol.

In another aspect of the invention, a polyether polyol can bemanufactured by reacting a poly alkylene oxide polyol with the glycidylcompound.

In a further aspect of the invention, a polyester polyol can be reactedwith the glycidyl compound of the invention. Substantially linearpolyester polyols of dicarboxylic acids and di hydroxyl compound can bemade with useful molecular weight and reactivity.

In a still further aspect of the invention, the capping agent can beused in a method for the manufacturer of a polyester polyol usingsubstantially linear polyester polyols of dicarboxylic acids and dihydroxyl compound such as an aliphatic dicarboxylic acid, and aliphaticdihydroxy compound in order to form a preliminary polyester reactionproduct. When that reaction product achieves molecular weight of atleast 500 or at least 2000, an acid number of 5 to 100 or, the precursorreaction product can be reacted with the glycidyl compound such as aglycidyl ester compound to complete the reaction and form the finishedcapped polymeric polyol material. In this way the reaction does not haveto be forced to completion as the concentration of the acid and hydroxylreactants are reduced. The amount of glycidyl compound is selected toreact with acid and hydroxyl functionality leaving a finished materialwith an acid number (less than or equal to 2 or less than 1) or hydroxylnumber (less than 6 or less than 12 or less than 112) and a residualglycidyl content of less than 0.1%, 0.05 or 0.02% for further use suchas in a urethane adhesive. Since the use of the glycidyl ester compoundthen reacts with available acid and hydroxyl material in the reactionproduct, then the polyol synthesis is rapidly brought to completion muchsooner than if left to simply finish by the esterificationpolymerization.

The invention is also directed to capped polymeric polyester polyolcomprising the reaction product of a polyester polyol having a molecularweight greater than about 500. The hydroxyl number can be consistentwith the levels disclosed herein. The glycidyl compound can have aformula:

wherein A is an ester or ether residue or moiety and O is oxygen andwherein A can be linear or branched, saturated or unsaturated, acyl,aliphatic or aromatic hydrocarbon radical having from 2 to 30 carbonatoms, wherein the polyol is reacted with the glycidyl compound at aratio of epoxy groups to hydroxyl groups as disclosed herein.Glycidyl Compounds

Glycidyl compound are shown in the structural formula I as:

wherein A is an ester or ether residue or moiety and O is oxygen. A canbe linear or branched, saturated or unsaturated, acyl, aliphatic oraromatic hydrocarbon radical having from 2 to 30 carbon atoms.Alternately, glycidyl compounds, which contain glycidyl groups bondeddirectly to nitrogen or sulfur (where O═S or N) atoms can be employed inthe process. Alkyl glycidyl ethers or esters or mixtures of alkylglycidyl ethers or esters containing the requisite C₂₋₃₀ or C₄₋₂₂ alkylsubstituents may be utilized for the preparation of the cappedmaterials.Glycidyl Ethers

Examples of alkyl glycidyl ethers include ethyl, butyl glycidyl ether,iso-butyl glycidyl ether, pentyl glycidyl ether, amyl glycidyl ether,hexyl glycidyl ether, ethyl hexyl glycidyl ether, iso-octyl glycidylether, n-decyl glycidyl ether, lauryl glycidyl ether, myristyl glycidylether, cetyl glycidyl ether, phenyl glycidyl ether benzyl etc.

Glycidyl Esters

Glycidyl esters are of the general structure set forth in structuralformula I are the reaction product of one or a mixture of saturatedmonocarboxylic acids, preferably the alkali or tertiary ammonium saltsthereof, and a halo-substituted monoepoxide.

Suitable saturated monocarboxylic acids which may be used to prepare theglycidyl esters are primary secondary and tertiary alkyl acids whereincontaining 2-20 carbon atoms, more preferably 2-12 carbon atoms.Suitable such acids include neodecanoic, neotridecanoic, and pivalicacids. A particularly preferred acid is a neodecanoic acid prepared bythe reaction of mono olefins averaging 8-40 carbon atoms in the moleculewith carbon monoxide and water.

Suitable halo-substituted mono-epoxides which may be used to prepare theglycidyl esters include epichlorohydrin, 1-chloro-2,3-epoxyhexane,1-chloro-2,3-epoxy-4-butyloctane, 1-chloro-2,3-epoxy heptane,3-chloro-4,5-epoxydodecane, 3-chloro-4,5 epoxynonane,1-chloro-2,3-epoxy-4-cyclohexyloctane and like materials.

Glycidyl esters of this type and their method of synthesis are wellknown in the art and are particularly described in the aforementionedU.S. Pat. No. 3,178,454 and U.S. Pat. No. 3,075,999.

Useful glycidyl esters are shown in U.S. Pat. No. 6,433,217 and arerepresented by the following formula II:

In the formula, R6 and R7 are typically linear or branched hydrocarbylor alkyl groups having from about one to about 20 carbon atoms. Whereinthe total carbon content of the branched alkali group of the acid groupof the glycidyl ester as from about 5 to 25 carbon atoms and for certainembodiments from about 9 to about 15 carbon atoms. The glycidyl estercompositions useful in the compositions and processes disclosed hereinare exemplified in the publication of Momentum entitled Cardura E10P.Polyol for Capping Reaction

Polyols can be polyether polyols, which are made by the reaction ofalkylene oxides or epoxides with active hydrogen containing startercompounds, or polyester polyols, which are made by the polycondensationof multifunctional carboxylic acids and multifunctional hydroxylcompounds.

Polyester Polyols

One useful class of polyester polyols are manufactured by the directpoly-esterification of high-purity diacids (or lower alcohol esters) andglycols, such as adipic acid and 1,4-butanediol at elevated temperatureuntil the desired molecular weight (about 500 to 8000) is achieved.Polyester polyols are usually more expensive and more viscous thanpolyether polyols, but they make polyurethanes with better solvent,abrasion, and cut resistance. Other polyester polyols are based ontrans-esterification (glycolysis) of poly(ethylene terephthalate) (PET)or dimethyl terephthalate (DMT) with glycols such as diethylene glycol.

Polyester polyol can be made from the following hydroxyl diols andtriols reacted with dicarboxylic acid materials.

Diols and triols used for polyester polyol synthesis Hydroxyl number,No. Polyol MW, daltons mg KOH/g Diols 1 Ethylene glycol (EG) 62.071807.6 2 Diethylene glycol (DEG) 106.12 1057.2 3 1,2 Propylene glycol(PG) 76.10 1474.3 4 1,4 Butanediol (BD) 90.12 1245.0 5 Neopentyl glycol(NPG) 104.0 1078.8 6 1,6 Hexanediol 118.18 949.3 73-methyl-1,5-pentanediol 118 950.8 (MPD) 8 1,9-Nonanediol (ND) 160 710.3Triols 1 Glycerol 92.10 1827.3 2 Tri-methylol propane (TMP) 122 1379.5

Aliphatic dicarboxylic acids used for polyester polyol synthesis Acidnumber, No. Dicarboxylic acid MW, Daltons mg KOH/g 1 Adipic acid (AA)146.14 767.78 2 Glutaric acid 132.12 849.2 3 Succinic acid 118.09 950.14 Sebacic acid 202.0 555.4 5 Azelaic acid 186.0 603.2 6 Dodecanedioicacid 230.3 487.2

Aromatic dicarboxylic acids and derivatives used for polyester polyolsynthesis Acid number, No. Dicarboxylic acid MW, daltons mg KOH/g 1Iso-phthalic acid (IPA) 166.13 675.3 2 Phthalic anhydride 148.12 757.4 3Terephthalic acid 166.13 675.3Polyether Polyol

Polyols use dipropylene glycol (functionality 2), glycerin(functionality 3) or a sorbitol/water solution (functionality 2.75),sucrose (functionality 8), sorbitol (functionality 6), toluene diamine(equivalent of 4 hydroxyl). Propylene oxide and/or ethylene oxide isadded to the initiators until the desired molecular weight (greater thanabout 500 or 8000) is achieved. The order of addition and the amounts ofeach oxide affect many polyol properties, such as compatibility,water-solubility, and reactivity. Polyols made with only propylene oxideare terminated with secondary hydroxyl groups and are less reactive thanpolyols capped with ethylene oxide, which contain a higher percentage ofprimary hydroxyl groups.

Polyether polyols can be represented by:

Wherein R₁ represents an initiator compound residue, R₂ is a C₂₋₄alkylene group and n is a number of 2 to 100. The group R₂—O— alsorepresents a polymer residue of polymerized ethylene oxide, propyleneoxide or mixtures thereof. Due to their high hydroxyl number dendriticpolyols are not useful in the claimed compositions.

Initiators used for the synthesis of polyols Molecular weight Hydroxylnumber Starter Functionality (Daltons) (mg KOH/g) Water 2 18 6233.3Ethylene glycol 2 62 1807.9 Diethylene glycol 2 106 1057.4 1,2 Propylene2 76.1 1474.6 glycol Dipropylene glycol 2 134.2 836.3 (DPG) Glycerin 392 1829 Tri-methylol 3 134.2 1254.1 propane 1,2,6 Hexanetriol 3 134 1255Triethanolamine 3 146 1152.7 Ethylenediamine 4 60 3740 Pentaerythritol 4136.15 1648.18Polymer Polyol Capping Reaction

The capping reaction combines a glycidyl compound with the polymerpolyol and reacts the glycidyl compound with a group with an activehydrogen such as a carboxylic acid (—CO₂H) or hydroxyl (—OH) group. Aresulting capped polyether structures can be represented as IVa or IVb:

Capped polyester is represented by Va or Vb:

wherein R₈O— represents the residue of —OH functionality of a polyetherpolyol or —OH functionality of a polyester polyol as structure VI:

represents a residue of the acid functionality of a polyester polyol.The glycidyl reaction creates secondary hydroxyls or primary hydroxylsdepending on the presence of catalyst that can react in a urethaneadhesive. Amounts of materials are selected such that the hydroxyl orcarboxylic acid functionality is fully reacted and made derivative by amatching amount of glycidyl compound. At the end of the reaction littleor no free carboxylic acid, epoxy or glycidyl functionality should bedetected.Adhesive Technology

The remaining active hydrogen groups, primarily hydroxyl groups, in thecapped polyols can be used to formulate curing adhesives. Any curingagent that can react with the active hydrogen or hydroxyl can be used inan adhesive. Useful adhesives are urethane and epoxy materials.

Polyurethanes are produced by reacting an isocyanate containing two ormore isocyanate groups with a polyol containing on average two or morehydroxyl groups per molecule typically in the presence of a catalyst.

Isocyanates are very reactive materials. Aromatic isocyanates,diphenylmethane diisocyanate (MDI) or toluene diisocyanate (TDI) aremore reactive than aliphatic isocyanates, such as hexamethylenediisocyanate (HDI) or isophorone diisocyanate (IPDI). Isocyanates aredifunctional; two isocyanate groups per molecule. An important exceptionto this is polymeric diphenyl methane diisocyanate, which is a mixtureof molecules with two-, three-, and four- or more isocyanate groups. Incases like this the material has an average functionality greater thantwo, commonly 2.7.

The capped polyols of the disclosure that are used to make polyurethaneadhesives are not “pure” compounds since they are often mixtures ofsimilar molecules with different molecular weights and mixtures ofmolecules that contain different numbers of hydroxyl groups, which iswhy the “average functionality” is often mentioned. The polymerizationreaction makes a polymer containing the urethane linkage, —RNHCOOR′— andis catalyzed by tertiary amines, such as 1,4-diazabicyclo [2.2.2] octane(also called DABCO or TEDA), DMDEE (2,2′-dimorpholino diethyl ether) andmetallic compounds, such as dibutyltin dilaurate or bismuth octanoate.

Aliphatic and cycloaliphatic isocyanates are used in smaller volumes,most often in coatings and other applications where color andtransparency are important. The most important aliphatic andcycloaliphatic isocyanates are 1,6-hexamethylene diisocyanate (HDI),1-isocyanato-3-isocyanatomethyl-3,5,5-trimethyl-cyclohexane (isophoronediisocyanate, IPDI), and 4,4′-diisocyanato dicyclohexyl methane, (H₁₂MDIor hydrogenated MDI).

Chain extenders are low molecular weight hydroxyl and amine terminatedcompounds that play an important role in the polymer morphology. Thechoice of chain extender also determines flexural, heat, and chemicalresistance properties. The most important chain extenders are ethyleneglycol, 1,4-butanediol (1,4-BDO or BDO), 1,6-hexanediol, cyclohexanedimethanol and hydroquinone bis(2-hydroxyethyl) ether (HQEE).

Polyurethane catalysts can be classified into two broad categories,amine compounds and metal complexes. Traditional amine catalysts havebeen tertiary amines such as triethylene diamine (TEDA,1,4-diazabicyclo[2.2.2]octane or DABCO), dimethyl cyclohexylamine(DMCHA), and dimethyl ethanolamine (DMEA). Tertiary amine catalysts areselected based on whether they drive the urethane (polyol+isocyanate, orgel) reaction or the isocyanate trimerization reaction (e.g., usingpotassium acetate, to form isocyanurate ring structure). Catalysts thatcontain a hydroxyl group or secondary amine, which react into thepolymer matrix, can replace traditional catalysts thereby reducing theamount of amine that can come out of the polymer.

Suitable additives for use in the present invention may be any compoundwhich will not interfere with the efficacy of the other components inthe adhesive composition and which increases adhesion. Suitableadditives include, but are not limited to, reactive or non-reactivepolymers, fillers, plasticizers, viscosity control agents, defoamers andstabilizers.

Exemplary Section

The following examples and data (reflected in the figures of theconversion of the materials into polyester) show the utility of theprocesses of the invention in obtaining high quality polyol materialsfor use in the compositions of the disclosure. The preparations areexemplary of the aspect of the invention using polyester polyolmaterials but should not be used in unduly limiting the scope of theclaims.

In the following polymerization reactions followed by the cappingreaction, the reactants are combined in a conventional oil jacketedheated polyester reactor vessel equipped with a nitrogen bubbler thatacts to remove volatile materials such a reaction byproduct water,reduce color formation and agitate the mixture.

In the formation of the capped polyester polyol, the dicarboxylic acidand the dihydroxyl compound is added to the vessel and heated to 140° C.Water a byproduct of esterification is formed and removed by nitrogen.After water generation slows, the temperature is gradually increased to220° C. and the reaction is continued until the acid number falls toless than 20 preferable less than 10. At this point the molecular weightis greater than about 3000.

The reaction mixture is cooled and the glycidyl ester is then added toreact with remaining acid groups. The reaction is heated to 140-190° C.This reaction forms secondary or primary hydroxyl groups with glycidylring opening.

Examples 1-6

Materials—

Adipic acid, CAS number 124-04-9, F.W. 146.14, melting point 150.85° C.,boiling point 337.5° C., flash point 196° C.; 1,6-hexanediol, CAS number6920-22-5, F.W. 118.18, melting point 40-42° C., boiling point 253-260°C., flash point 135° C. (Tag Closed Cup); Glycidyl ester Cardura E10P,boiling range 251-278° C. (5-95%), epoxide equivalent 240 g/mol,viscosity 7 mPa/s (23° C.), high flash point.

Synthesis of Polyester Precursor

Molar ratio between hydroxyl and carboxyl EX. 1-6 Adipic Acid (g)1,6-Hexanediol (g) groups Polyester 9, 900 (54.44 wt %) 753 (45.56 wt %)1.035:1 11, 15, 16L, 16R Polyester 13 900 (56.07 wt %) 705 (43.93 wt%)0.969:1

753 g of 1,6-hexanediol (for polyester 9, 11, 15, 16L and 16R) and 900 gof adipic acid were reacted under a nitrogen atmosphere at a temperaturein the range from 140 to 200° C. After water which had been formed inthe reaction had been removed by distillation, the temperature wasincreased to range from 200-230° C. After the acid number had fallen tothe expected data, the reaction was stopped. Then we measured the acidnumber and viscosity.

Acid Mn (calculated Brookfield Viscosity Number from (cP, 80° C.,spindle #31, EX. 1-6 (mg KOH/g) theory) 20 rpm) Polyester 9  8.22 (12 h)3389 2432 Polyester 11  9.10 (13 h) 3219 2064 Polyester 15 11.70 (12 h)2802 1360 Polyester 16L 10.16 (14 h) 3035 N/A Polyester 16R 10.56 (14 h)2971 N/A Polyester 13 27.24 (9 h) 2881 1600Capping Reaction

$W_{E\; 10\; P} = {\frac{W_{polyester}*{AN}}{56110}*240\mspace{14mu}(g)}$

Reaction Proportions

Acid OH number Number of of polyester polyester (mg W_(polyester) EX.1-6 (mg KOH/g) KOH/g) (g) W_(E10P) (g) Polyester 9 8.22 24.89 1221 42.93(3.37%) Polyester 11 9.10 25.77 1272 49.51 (3.75%) Polyester 15 11.7028.35 1336 66.86 (4.77%) Polyester 10.16 26.82 1436 62.40 (4.16%) 16LPolyester 10.56 27.22 1436 64.86 (4.32%) 16R Polyester 13 27.24 11.721289 150.19 (10.44%)

Polyester precursor was heated to 160° C. in nitrogen atmosphere, andthen Cardura E10P was added into the reactor in 30 minutes in droplets.The reaction temperature was increased to 190° C. in 3 hours and holdfor 3 hours.

Brookfield OH number of Mn Viscosity (cP, Acid Number polyester (mg(calculated from 80° C., spindle #31, EX. 2-6 (mg KOH/g) KOH/g) theory)20 rpm) Polyester 11 0.93 (8.76) 32.63 (24.80) 3344 (3219) 2256Polyester 15 1.22 (11.14) 36.92 (27.00) 2942 (2802) 1472 Polyester 16L0.86 (9.73) 34.57 (25.70) 3167 (3035) 1856 Polyester 16R 1.11 (10.10)35.03 (26.04) 3105 (2971) 1696 Polyester 13 2.00 (24.40) 32.90 (10.50)3215 (2881) 1632

The reaction time of polyester precursor can be shortened from greaterthan 20 hours to to 15 hours or less. The reaction temperature ofpolyester precursor ranges from 140 to 230° C. and holding at 220-230°C. for not less than 9 hours. The reaction of acid carboxyl with epoxyis stoichiometric. Final reaction temperature ranges from 160-190° C.The residual epoxy in the final products is less than 0.02 mmol/g (epoxyresidue is 0.032%). FIG. 1 shows the viscosity of the precursorpolyester and the capped polyester.

Example 7

Materials—

Adipic acid, CAS number 124-04-9, F.W. 146.14, melting point 150.85° C.,boiling point 337.5° C., flash point 196° C.; 1,6-hexanediol, CAS number6920-22-5, F.W. 118.18, melting point 40-42° C., boiling point 253-260°C., flash point 135° C. (Tag Closed Cup); Cardura E10P, boiling range251-278° C. (5-95%), epoxide equivalent 240 g/mol, viscosity 7 mPa/s(23° C.), high flash point.

Synthesis of Polyester Precursor

Molar ratio between hydroxyl and carboxyl EX. 7 Adipic Acid (g)1,6-Hexanediol (g) groups Polyester 17 12910 (54.45 wt %) 10800 (45.55wt %) 1.0345:1Reaction Procedure

10800 g of 1,6-hexanediol and 12910 g of adipic acid were reacted undera nitrogen atmosphere at a temperature in the range from 140 to 200° C.(in 5 hours). After most of the water which had been formed in thereaction had been removed by distillation, the temperature was increasedto range from 220-230° C. (in 2 hours) and hold for 8.5 hours. After theacid number had fallen to the expected data, the reaction was stopped.Measure the acid number.

Results

Acid Number Mn EX. 7 (mgKOH/g) (calculated from theory) Polyester 177.95 (15.5 h) 3452Synthesis Determination of the Dosage of Cardura E10P

$W_{E\; 10\; P} = {\frac{W_{polyester}*{AN}}{56110}*240\mspace{14mu}(g)}$Recipes

Acid OH Number of number of polyester polyester EX. 7 (mgKOH/g)(mgKOH/g) W_(polyester) (g) W_(E10P) (g) Polyester 17 7.95 24.56 20581697.4 (3.28%)Reaction Procedure

Polyester precursor was cooled to 140° C. in nitrogen atmosphere, thenCardura E10P was added into the reactor in 20 minutes. The reactiontemperature was increased to 180° C. in 2 hours and hold for 2 hours.Stop the reaction when the acid number below 1 mgKOH/g.

Results

Brookfield Mn Viscosity (cP, Acid OH number of (calculated 80° C.,Number polyester from spindle #31, EX. 7 (mgKOH/g) (mgKOH/g) theory) 20rpm) Polyester 17 0.45 31.03 3565 3536

Reaction condition of polyester 17 (See FIG. 2 for graphicalrepresentation)

Reaction time Condensor H2O (hr) Outside T ° C.) Inside T (° C.) T (°C.) wt. (g) −0.75 160.0 112 24 0 −0.5 160.0 122 25 0 −0.2 160.0 139 30 0−0.08 165.6 137.7 74 0 0 165.6 136.8 95.3 0 0.5 168.3 139.5 98.5 350 1173.9 140.4 96.2 815 1.5 179.4 148.1 92.6 1275 2 189.4 154.5 91.7 15752.5 199.4 167.5 91.7 1865 3 205.0 177.7 90.2 2090 3.5 210.6 186.2 85.82310 4 215.6 192.1 82.6 2410 4.5 221.1 197.1 77.3 2480 5 226.7 200.5 742530 5.5 232.2 206.1 71.5 2580 6 237.8 212.2 67.4 2615 7 237.8 221 63.12660 10 243.3 224.7 46 2780 12 243.3 224.4 38.8 2812 13 243.3 224.7 36.42825 15 243.3 223.6 34.1 2842 15.5 243.3 224 33 2846Conclusion

The reaction time of polyester precursor can be shortened into 16 hours.

Reaction temperature of polyester precursor is range from 140 to 230° C.and holding at 220-230° C. for 8˜9 hours.

The reaction of carboxyl with epoxy is in stoichiometry. Reactiontemperature ranges from 140-180° C. Reaction time is around 5 hours.

The residual epoxy group in the final products is less than 0.02 mmol/g(epoxy residue is 0.032%).

Adhesive Examples

g Adhesive Example 1 eq. wt. % wt OH NCO 800 1 Poly propylene glycol15.750 1000 15.7500% 0.0158 x 126.00 PPG2000 2 Capped Polyester 1122.000 1750 22.0000% 0.0126 x 176.00 3 Linear saturated Dynacol 17.5002550 17.5000% 0.0069 x 140.00 7250 polyester polyol EG/Hexane diolneopentyl glycol adipic acid ester 4 CAPA5600 Capro-lactone 10.000 2500010.0000% 0.0004 x 80.00 polyester 5 3500 HAT Hexane diol 22.000 175022.0000% 0.0126 x 176.00 adipic acid terephthalic acid ester 6 BYK070defoamer 0.100 10000000  0.1000% 0.0000 x 0.80 7 MDI 12.600 125 12.6000%x 0.1008 100.80 8 DMDEE 0.050 10000000  0.0500% x x 0.40(2,2′-dimorpholino diethylether  100.00% 800.00 100.0000 NCO %   2.21%0.0482 0.1008

g Adhesive Example 2 eq. wt. % wt OH NCO 800 1 PPG2000 15.750 100015.7500% 0.0158 x 126.00 2 Capped polyester 13 22.000 1750 22.0000%0.0126 x 176.00 3 Dynacol7250 17.500 2550 17.5000% 0.0069 x 140.00 4CAPA5600 10.000 25000 10.0000% 0.0004 x 80.00 5 3500HAT 22.000 175022.0000% 0.0126 x 176.00 6 BYK070 0.100 10000000  0.1000% 0.0000 x 0.807 MDI 12.600 125 12.6000% x 0.1008 100.80 8 DMDEE 0.050 10000000 0.0500% x x 0.40  100.00% 800.00 100.0000 NCO %   2.21% 0.0482 0.1008

Comparative Adhesive g Example eq. wt. % wt OH NCO 800 1 PPG2000 15.7501000 15.7500% 0.0158 x 126.00 2 3500 molecular weight 22.000 175022.0000% 0.0126 x 176.00 hexane-adipic acid polyester polyol 3Dynacol7250 17.500 2550 17.5000% 0.0069 x 140.00 4 CAPA5600 10.000 2500010.0000% 0.0004 x 80.00 5 3500HAT 22.000 1750 22.0000% 0.0126 x 176.00 6BYK070 0.100 10000000  0.1000% 0.0000 x 0.80 7 MDI 12.600 125 12.6000% x0.1008 100.80 8 DMDEE 0.050 10000000  0.0500% x x 0.40  100.00% 800.00100.0000 NCO %   2.21% 0.0482 0.1008

Adhesive Ex Visc (250° F.) cP Open time, Sec, Bond ABS/Wood 1 18850 70Good 2 16480 100 Good Comparative 17120 60 N/A

Comp. Ex. and Examples 1 and 2 are same percentage but Comp. Ex. is withstraight molecular weight hexane-adipic acid polyester polyol Ex. 1 iswith Polyester 11 (with 3-4% Cardura) and Ex. 2 is with 10% Carduracapped polyester polyols. In the case of 22% polyester polyols in theformula, with low level Cardura (3-4%), the physical property are almostthe same as regular polyester polyol. With higher Cardura, the finishedviscosity is a little lower but with longer open time, which is becausethe Cardura use reduces the crystalline behavior. Lower viscosity andlonger open time are often desired in process or in application.

As can be seen in the tables of data, the processes using thecompositions disclosed above produce quality polyester polyol materialsin a shortened period of time with substantially complete conversion toa useful polyol material with minimal residual acid or hydroxyl minimalresidual acid functionality. The hydroxyl functionality of the polyolremains since in the reaction between the glycidyl ether or glycidylester materials and the polyol a new hydroxyl group is formed in thereaction that remains available for reaction with the isocyanatecompound in a urethane adhesive.

The claims may suitably comprise, consist of, or consist essentially of,or be substantially free of any of the disclosed or recited elements.The invention illustratively disclosed herein can also be suitablypracticed in the absence of any element which is not specificallydisclosed herein. The various embodiments described above are providedby way of illustration only and should not be construed to limit theclaims attached hereto. Various modifications and changes may be madewithout following the example embodiments and applications illustratedand described herein, and without departing from the true spirit andscope of the following claims

I claim:
 1. A method for the synthesis of a capped polyester polyol, themethod comprising the steps of: (a) combining a polyester polyol havinga molecular weight of at least 500 with a glycidyl compound at a ratioof one glycidyl compound per each active hydroxyl group in the polyesterpolyol to form a mixture, wherein the polyester polyol is a reactionproduct of a carboxylic acid with a carboxyl functionality of two ormore and a hydroxyl compound with a hydroxyl functionality of two ormore, and the glycidyl compound comprises a glycidyl ether or glycidelester compound; and (b) reacting the polyester polyol with the glycidylcompound to form the capped material.
 2. The method of claim 1, whereinthe polyester polyol comprises a substantially linear aliphaticpolyester.
 3. The method of claim 2, wherein the aliphatic polyester isa reaction product of dicarboxylic acid and a diol.
 4. The method ofclaim 1, wherein the polyester polyol is a reaction product of anaromatic dicarboxylic acid and a diol.
 5. The method of claim 1, whereinthe glycidyl ester comprises a carboxylic acid ester having 5 to 20carbon atoms.
 6. The method of claim 5, wherein the glycidyl estercomprises a compound of formula:

wherein, R6 and R7 comprises linear or branched alkyl groups having fromabout one to about 20 carbon atoms.
 7. The method of claim 6, whereinthe total carbon content of the branched alkyl group of the acid groupof the glycidyl ester is such from about 9 to about 15 carbon atoms. 8.A method for the synthesis of a capped polyester polyol, the methodcomprising the steps of: (a) forming a polyol from an aliphaticcarboxylic acid with a carboxyl functionality of two or more and analiphatic hydroxyl compound with a hydroxyl functionality of two or moreto form a polyester polyol having a molecular weight of at least 500 byreacting the acid with the hydroxyl compound, at temperature greaterthan 190° C., to form a reaction mixture, until the acid number of thereaction mixture is less than 0.5; and (b) reacting the polyester polyolwith a glycidyl ester at a temperature greater than 140° C. to form thecapped material.
 9. A polyurethane adhesive material comprising areaction product of an isocyanate compound and the capped polyesterpolyol made by the method of claim
 8. 10. The polyurethane adhesivematerial of claim 9, wherein the isocyanate compound is MDI.